The genetics of nuclear pre-mRNA splicing: a complex story

Abstract
The occurrence of introns in nuclear precursor RNAs (pre-mRNAs) is widespread in eukaryotes, and the splicing process that removes them is basically the same in yeasts as it is in higher eukaryotes. Splicing takes place in a very large, multi-component complex, the spliceosome, and biochemical studies have been complicated by the large number of splicing factors involved. This review describes how genetic approaches used to study RNA splicing inSaccharomyces cerevisiae have complemented the biochemical studies and led to rapid advances in the field.